Air Distribution Device of Single Fan Type Air Purifier

ABSTRACT

An air circulation device for an air purifier includes an air passage apparatus which includes an air passage body having a first air outlet and a second air outlet formed in an opposing manner and defining an air passage between the first air outlet and the second air outlet, and an air flow generating unit mounted to the single fan unit in the air passage body and configured to draw air inletting into the air passage and form an air flow flowing towards the first air outlet and the second air outlet. The air circulation device further includes an air distribution member disposed in the air passage body and configured to provide different air outlet flowing speeds at the first air outlet and the second air outlet.

CROSS REFERENCE OF RELATED APPLICATION

This application is a non-provisional application that claims the benefit of priority under 35 U.S.C. § 119 to a Chinese invention application number CN202110640194.1, filed Jun. 9, 2021, which is incorporated herewith by reference in its entirety.

NOTICE OF COPYRIGHT

A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to any reproduction by anyone of the patent disclosure, as it appears in the United States Patent and Trademark Office patent files or records, but otherwise reserves all copyright rights whatsoever.

BACKGROUND OF THE PRESENT INVENTION Field of Invention

The present invention relates to desktop air purifier, and more particularly to an air distribution device of a single fan type air purifier which is configured to accelerate the air circulation to enhance a purification speed within a local space by providing an air vortex between a pair of air outlets due to a formation of an air flow speed difference at the pair of air outlets.

Description of Related Arts

Air purifier is an electrical device for removing indoor solid pollutants and gaseous pollutants in air. Referring to FIG. 1 , desktop air purifier having a size around 35 cm×20 cm×60 cm is commonly used in indoor area which is generally placed on a desktop or a floor around a living area and dining area for purifying air around a limited area such as 15 m² to 30 m². Such desktop air purifier generally comprises a single fan unit 11 configured to circulating air therearound to force air flowing in via an air inlet 101 and flowing through an air purifying unit 12 to remove and absorb air pollutants and a negative ion generator 13 to ionize the air passing through to produce a large number of negative ions in the air flow to be delivered back to the surrounding area through an air passage unit 111 by means of the single fan unit 112 of an air circulation device 11.

It is known that there are more than 500 kinds of volatile organic compounds in the door air, including more than 20 kinds of carcinogens, more than 200 kinds of pathogenic viruses, and various hazards compounds such as radon, formaldehyde, benzene, ammonia, esters, trichloroethylene, and etc. Indoor air pollution is one of the causes of more than 50% of diseases. World Health Organization (WHO) has confirmed that formaldehyde causes cancer and induces leukemia in children, especially the air pollution after interior renovation. The clean air delivery rate (CADR) is a performance index for air purifiers and reflects their purification capacity.

Therefore, beside the capability and performance of the purifying units, the capability and performance of the air circulation device is an essential factor for providing better air flow. However, the conventional single fan type air circulation device basically provides a single air outlet that fails to produce microcirculation for the purified air.

SUMMARY OF THE PRESENT INVENTION

The invention is advantageous in that it provides an air passage apparatus of a single fan type air circulation device for air purifier, which accelerates air circulation to enhance a purification speed within a designated area.

Another advantage of the invention is to provide an air passage apparatus of a single fan type air circulation device for air purifier, which has a pair of air outlets and provides an air vortex in a local space around a pair of air outlets.

Another advantage of the invention is to provide an air passage apparatus of a single fan type air circulation device for air purifier, which is configured to form an air flow speed difference at the pair of air outlets.

Another advantage of the invention is to provide an air passage apparatus of a single fan type air circulation device for air purifier, which is configured to form an air pressure difference at the pair of air outlets.

Another advantage of the invention is to provide an air passage apparatus of a single fan type air circulation device for air purifier, which can selectively provide an air flow speed difference in dual directions, leftwards or rightwards.

Another advantage of the invention is to provide an air passage apparatus of a single fan type air circulation device for air purifier, which can expand an air outlet range and form a microcirculation of air flow within a local space around a pair of air outlets of the air purifier.

Another advantage of the invention is to provide an air passage apparatus of a single fan type air circulation device for air purifier, which can selectively provide a leftward air circulation and a rightward air circulation within a local space around a pair of air outlets of the air purifier.

Additional advantages and features of the invention will become apparent from the description which follows, and may be realized by means of the instrumentalities and combinations particular point out in the appended claims.

According to the present invention, the foregoing and other objects and advantages are attained by an air circulation device for an air purifier comprising a single fan unit, wherein the air circulation device comprises:

an air passage apparatus comprising:

an air passage body having a first air outlet and a second air outlet formed in an opposing manner and defining a circular air passage between the first air outlet and the second air outlet, and

an air flow generating unit mounted to the single fan unit in the air passage body and configured to draw air inletting into the air passage and form an air flow flowing towards the first air outlet and the second air outlet; and

an air distribution device movably disposed in the air passage body and configured to selectively provide different air outlet flowing speeds at the first air outlet and the second air outlet and different air outlet pressures at the first air outlet and the second air outlet.

In one embodiment, the air distribution device comprises an air distribution member movably supported between the first air outlet and the second air outlet in the air passage body in such a manner that:

(i) when the air distribution member is positioned in a neutral position, an amount of air flowing out of the first air outlet and an amount of air flowing out of the second air outlet are the same,

(ii) when the air distribution member is positioned in a first circulation position, the amount of air flowing out of the second air outlet is larger than the amount of air flowing out of the first air outlet, and

(iii) when the air distribution member is positioned in a second circulation position, the amount of air flowing out of the first air outlet is larger than the amount of air flowing out of the second air outlet.

In accordance with another aspect of the invention, the present invention comprises a method of controlling air circulation of an air purifier, comprising:

distributing a larger portion of air flow flowing out through one of a pair of air outlets than another one of the pair of air outlets of an air circulation device of the air purifier to form an air flow speed difference between the pair of air outlets to accelerate air circulation and provide an air vortex in a local space around the pair of air outlets.

In one embodiment, the method of controlling air circulation of an air purifier, further comprising:

selectively positioning an air distribution member at a neutral position, a first circulation position or a second circulation position, wherein in the neutral position, the amount of air flowing out of the first air outlet and an amount of air flowing out of the second air outlet are the same, wherein in the first circulation position, the amount of air flowing out of the first air outlet is larger than the amount of air flowing out of the second air outlet, wherein in the second circulation position, the amount of air flowing out of the second air outlet is larger than the amount of air flowing of the first air outlet.

Still further objects and advantages will become apparent from a consideration of the ensuing description and drawings.

These and other objectives, features, and advantages of the present invention will become apparent from the following detailed description, the accompanying drawings, and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of an air purifier.

FIG. 2 is a perspective view of an air passage apparatus and a single fan unit of an air circulation device for air purifier, illustrating an air circulation member of an air distribution in a neutral position, according to a preferred embodiment of the present invention.

FIG. 3 is a plan view of the air circulation device for air purifier, illustrating the air distribution member is in the neutral position, according to the above preferred embodiment of the present invention.

FIG. 4 is a perspective view of the air circulation device for air purifier, illustrating the air circulation member is in a first circulation position, according to a preferred embodiment of the present invention.

FIG. 5 is a plan view of the air circulation device for air purifier, illustrating the air circulation member is in the first circulation position, according to the above preferred embodiment of the present invention.

FIG. 6 is a perspective view of the air circulation device for air purifier, illustrating the air circulation member is in a second circulation position, according to a preferred embodiment of the present invention.

FIG. 7 is a plan view of the air circulation device for air purifier, illustrating the air circulation member is in the second circulation position, according to the above preferred embodiment of the present invention.

FIG. 8 is a perspective schematic view of the air circulation device for air purifier according to the above preferred embodiment of the present invention.

FIG. 9 is another perspective schematic view of the air circulation device for the air purifier according to the above preferred embodiment of the present invention.

FIG. 10 is an exploded schematic view illustrating the single fan unit and the air flow generating unit of the air circulation device for the air purifier according to the above preferred embodiment of the present invention.

FIG. 11 is a perspective schematic view illustrating the air passage body with the air distribution member of the air distribution device for the air purifier according to the above preferred embodiment of the present invention.

FIG. 12 is another perspective schematic view illustrating the air passage body with the air distribution member of the air distribution device for the air purifier according to the above preferred embodiment of the present invention.

FIG. 13 is a perspective schematic view illustrating the air flow generating unit in the air passage body of the air distribution device for the air purifier according to the above preferred embodiment of the present invention.

FIG. 14 is a rear schematic view illustrating an air inlet of the air circulation device for the air purifier according to the above preferred embodiment of the present invention.

FIG. 15 is a perspective view of an air purifier installed with an air circulation device according to the above preferred embodiment of the present invention.

The drawings, described above, are provided for purposes of illustration, and not of limitation, of the aspects and features of various examples of embodiments of the invention described herein. The drawings are not intended to limit the scope of the claimed invention in any aspect. For simplicity and clarity of illustration, elements shown in the drawings have not necessarily been drawn to scale and the dimensions of some of the elements may be exaggerated relative to other elements for clarity.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The following description is disclosed to enable any person skilled in the art to make and use the present invention. Preferred embodiments are provided in the following description only as examples and modifications will be apparent to those skilled in the art. The general principles defined in the following description would be applied to other embodiments, alternatives, modifications, equivalents, and applications without departing from the spirit and scope of the present invention.

It will be appreciated that numerous specific details are set forth in order to provide a thorough understanding of the exemplary embodiments described herein. However, it will be understood by those of ordinary skill in the art that the embodiments described herein may be practiced without these specific details. In other instances, well-known methods, procedures and components have not been described in detail so as not to obscure the embodiments described herein. Further, this description is not to be considered as limiting the scope of the embodiments described herein in any way, but rather as merely describing implementation of the one or more embodiments described herein.

The present invention provides an air circulation device 20 for a single fan type air purifier, wherein the air purifier, like the traditional air purifier as illustrated in FIG. 1 , generally comprises a housing 10 having at least an air inlet window 101 and at least an air outlet window 102, a single fan unit 30, an air purifying unit 12 arranged before the air circulation device 20 in the housing 10, a negative ion generator 12 arranged in an upper position before the air circulation device 20 in the housing 1, and a control panel 14 arranged on the housing 10 and electrically connected to an external or internal power supply and the air circulation device 20 so as to control the activation of a single fan unit 30 mounted in the air circulation device 20 to selectively generate a suction force to draw air flowing therethrough to form an air flow passage, flowing from the air inlet 101 to the air outlet window 102. Therefore, outside air is drawn into the air purifier to pass through the air purifying unit 12 for purifying and then the purified air is ionized by the negative ion generator 12 inside the housing. The purified and ionized air is forced to further flow through the air circulation device 20 and distributed in a predetermined way to flow out via the air outlet window 102 to the outside of the air purifier.

According to a preferred embodiment of the present invention, referring to FIGS. 2 to 14 , the improvement of the present invention is the air circulation device 20 which comprises a configuration to accelerate air circulation to enhance a purification speed of the air flow of the purified and ionized air and provide an air vortex in a local space. Referring to FIG. 10 , the air circulation device 20 comprises an air passage body 21, an air flow generating unit 22 and an air distribution device 23.

The air passage body 21 of the air circulation device 20, referring to FIGS. 11-12 and 14 , comprises a passage frame 211, shaped and configured according to the model of the air purifier to be fitted and mounted securely in the housing 10 of the air purifier, an air passage house 212, an air passage guider 213 surrounding the air passage house 212 to define an air passage chamber 214, wherein the passage house 212 has an air inlet 215.

According to the preferred embodiment, the passage house 212 has a slightly concaved smooth bottom surface 2121 and the air passage guider 213 comprises a C-shaped curved guider wall portion 2131 and an outlet wall portion 2132 integrally extended outwardly from an open end of the curved boundary wall portion 2131 to form an enlarged air outlet opening 2133 divided by the air distribution device 23 to form a first air outlet 241 and a second air outlet 242 in opposing manner at a right side and a left side of the air chamber 214 respectively.

Referring to FIG. 13 , the air flow generating unit 22 is arranged rotatably at a position of the air inlet 215 within the air passage chamber 214 of the air passage house 212. The air flow generating unit 22 comprises a fan frame 221 having a motor cavity 2211 and a tubular motor shaft engaging element 2212 and a fan body 223 which includes a plurality of fan blades 2231 inclinedly and outwardly extended from a circular frame wall 2213.

FIG. 10 is an exploded schematic view illustrating the single fan unit 30 and the air flow generating unit 22 of the air circulation device 20 for the air purifier according to the above preferred embodiment of the present invention. It is noted that X-Y-Z or XC-YC-ZC in FIGS. 8 to 13 is coordinates of the figure but not a part of the air circulation device 20 and the air passage body 21 is shown in lighter color to illustrate the positioning relationship of the air passage body 21, the single fan unit 30 and the air flow generating unit 22.

Referring to FIG. 10 , the single fan unit 30 comprises a fan motor mount 31 and a fan motor 32 having a rotation shaft 321 (illustrated in dotted line). The fan motor mount 31 comprises a mount frame 310, a circular mount body 311 having a recessed motor cavity 312 and a central shaft hole 313, and a pair of first and second opposing mounting members 314, 315 radially extended from the mount frame 310 in opposite directions outwardly, wherein the fan motor 32 is received in the motor cavity 312 while the rotation shaft 321 is penetrated through the central shaft hole 313. The fan motor mount 31 is fastened to the housing 10 so as to mount the fan motor 32 in a position coaxially with the air flow generating unit 22, such that the mount body 311 is inserted into the motor cavity 2211 of the air flow generating unit 22 and the motor shaft 321 is engaged with the motor shaft engaging element 2212 and thus a rotation of the motor shaft 321 driven by the fan motor 32 drives the air flow generating unit 22 to rotate through the motor shaft engaging element 2212. In addition, the engagement of the motor shaft 321 and the motor shaft engaging element 2212 also securely mounts the air flow generating unit 22 in a rotatable manner between the fan motor mount 31 and the air passage body 21, wherein a space between the air flow generating unit 22 and the air passage guider 213 is defined as a curved air passage 210, generally having a semi-circular C-shape, around the air flow generating unit 22 and communicating with the first air outlet 214 and the second air outlet 215, as shown in FIG. 13 . Referring to FIGS. 10 and 13 , the rotation of the air flow generating unit 22 generates an air flow, drawing outside air through the air inlet 215 into the air passage 210.

Referring to FIGS. 8 to 13 , the air distribution device 23 comprises a distribution mount 231 shaped and configured to be fastened to the mount body 311 of the fan unit 30 and an arc-shaped air distribution member 232 integrally extended downwardly into the air passage 210 of the air flow generating unit 21. The distribution mount 231 is arranged to be supported above the air flow circulation unit 21 coaxially and comprises a pair of first and second mounting wings 2311, 2312 opposingly extended outwardly in opposite directions corresponding to the mounting members 314, 315 respectively. The air distribution member 232 can be integrally formed at the first mounting wing 2311 of the distribution mount 231 perpendicularly. Or, according to the preferred embodiment, the air distribution member 232 is a curved panel fastened to an end of the first mounting wing 2311 of the distribution mount 231 perpendicularly.

The air distribution device 23 is arranged to be selectively supported coaxially above the air flow circulation unit 22 while the air distribution member 232 is able to be selectively positioned at a middle portion of the outlet opening 2133 so as to dividing the outlet opening 2133 to the first air outlet 241 and the second air outlet 242, wherein the air distribution member 232 is embodied to be selectively positioned in a neutral position, a first circulation position and a second circulation position.

Referring to FIGS. 2 to 3 , when the air distribution member 232 is operated to position in the neutral position, the first air outlet 241 and the second air outlet 242 has the same size, and thus the amount of air flowing out of the first air outlet 241 and the amount of air flowing out of the second air outlet 242 are the same.

Referring to FIGS. 4 to 5 , when the air distribution member 232 is operated to be positioned in the first circulation position, the size of the first air outlet 241 is smaller than the size of the second air outlet 242, and thus the amount of air flowing out of the second air outlet 242 is larger than the amount of air flowing out of the first air outlet 241.

Referring to FIGS. 6 to 7 , when the air distribution member 232 is operated to be positioned in the second circulation position, the size of the first air outlet 241 is larger than the size of the second air outlet 242, and thus the amount of air flowing out of the first air outlet 241 is larger than the amount of air flowing out of the second air outlet 242.

It is appreciated that by arranging the air distribution member 232 in the first circulation position or the second circulation position as illustrated in FIGS. 4 to 7 , the outletting air flowing in the air passage 210 is distributed to have a larger portion of air flow flowing out through one of the pair of first and second air outlets 241, 242 than another one of the pair of first and second air outlets 241, 242 such that an air flow speed difference and/or an air flow pressure difference is occurred between the first and second air outlets 242, 242 that substantially accelerates air circulation and provides an air vortex in a local space around the pair of the first and second air outlets 241, 242.

It is worth mentioning that the selection of the arrangement of the air distribution member 232 in the first circulation position as shown in FIGS. 4 and 5 or in the second circulation position as shown in FIGS. 6 and 7 depends on the surrounding environment where the air purifier is placed. Also, in the FIGS. 2 to 7 , only the air distribution member 232 of the air distribution device 23 is shown for purpose of illustrating various positions thereof.

The positioning of the air distribution member 232 can be operated by rotating the air distribution device 23 about the center of the air flow generating unit 22 manually by the user. Person skilled in the art would understand that the position of the air distribution member 232 can also be factory built-in position, and that the configuration and size of the air distribution member 232 can also be modified to desired configuration, shape and size with respect to the configuration of the air passage body 21 and the shape and size of the air passage 210 as long as substantially forming the first air outlet 241 and the second air outlet 242 while providing the air flow speed and/or pressure difference at the first and second air outlets 241, 242.

According to the preferred embodiment of the present invention, the air distribution device 23 is mounted in position selectively by fastening to the fan motor mount 31. Referring to FIGS. 8 to 10 , each of the first and second mounting wings 2311, 2312 of the distribution mount 231 provides three sets of mounting site A, B, C, as shown in FIG. 8 , each having the same size. The mounting site A of the two mounting wings 2311, 2312 is in a neutral position, the mounting site B of the two mounting wings 2311, 2312 is arranged having a counterclockwise angle with the mounting site A, and the mounting site C of the two mounting wings 2311, 2312 has a clockwise angle with the mounting site A. Accordingly, when the two mounting members 314, 315 of the fan motor mount 31 are aligned and fastened with the two mounting wings 2311, 2312 respectively at the mounting site A, the air distribution member 232 is positioned in the neutral position as shown in FIGS. 2 and 3 . When the two mounting members 314, 315 of the fan motor mount 31 are aligned and fastened with the two mounting wings 2311, 2312 respectively at the mounting site B, the air distribution member 232 is positioned in the first circulation position as shown in FIGS. 4 and 5 . When the two mounting members 314, 315 of the fan motor mount 31 are aligned and fastened with the two mounting wings 2311, 2312 respectively at the mounting site C, the air distribution member 232 is positioned in the second circulation position as shown in FIGS. 6 and 7 . The air distribution member 232 and the fan motor mount 31 can be fastened by screws or other fastening means. In other embodiments, the air distribution member 232 can be selectively arranged in one or more desired positions by other alternative methods which should not be considered as a limitation to the scope of the claimed invention.

By means of the air circulation device 20, as another aspect of the present invention, the present invention further provides a method of controlling air circulation of an air purifier, comprising:

distributing a larger portion of air flow flowing out through one of the pair of first and second air outlets 241, 242 than another one of the pair of first and second air outlets 241, 242 of the air circulation device 20 of the air purifier to form an air flow speed difference between the pair of air outlets 241, 242 to accelerate air circulation and provide an air vortex in a local space around the pair of air outlets 241, 242.

In one embodiment, the method of controlling air circulation of an air purifier further comprises selectively positioning the air distribution member 232 at the neutral position, the first circulation position or the second circulation position, wherein in the neutral position, the amount of air flowing out of the first air outlet 241 and the second air outlet 242 is the same, wherein in the first circulation position, the amount of air flowing out of the first air outlet 241 is larger than the amount of air flowing out of the second air outlet 242, wherein in the second circulation position, the amount of air flowing out of the second air outlet 242 is larger than the amount of air flowing of the first air outlet 241.

Referring to FIG. 15 , an example of a housing of an air purifier to be installed with the air circulation device 20 according to the preferred embodiment of the present invention is illustrated, wherein a pair of outlet air windows 102 is provided on the housing 10 at positions corresponding to and communicating with the first air outlet 241 and the second air outlet 242 of the air circulation device 20 installed therein.

One skilled in the art will understand that the embodiment of the present invention as shown in the drawings and described above is exemplary only and not intended to be limiting.

It will thus be seen that the objects of the present invention have been fully and effectively accomplished. The embodiments have been shown and described for the purposes of illustrating the functional and structural principles of the present invention and is subject to change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims. 

What is claimed is:
 1. An air circulation device for an air purifier which comprises a housing and a single fan unit, comprising: an air passage apparatus comprising: an air passage body having a first air outlet and a second air outlet formed in an opposing manner and defining an air passage between the first air outlet and the second air outlet, and an air flow generating unit mounted to the single fan unit in the air passage body and configured to draw air inletting into the air passage and form an air flow flowing towards the first air outlet and the second air outlet; and an air distribution member disposed in the air passage body and configured to provide different air outlet flowing speeds at the first air outlet and the second air outlet.
 2. The air circulation device, as recited in claim 1, wherein the air distribution device is arranged to provide different air outlet flowing pressures at the first air outlet and the second air outlet.
 3. The air circulation device, as recited in claim 1, wherein the air distribution member is movably supported between the first air outlet and the second air outlet in the air passage body such that when the air distribution member is positioned in a first circulation position, the amount of air flowing out of the second air outlet is larger than the amount of air flowing out of the first air outlet.
 4. The air circulation device, as recited in claim 2, wherein the air distribution member movably is supported between the first air outlet and the second air outlet in the air passage body such that when the air distribution member is positioned in a first circulation position, the amount of air flowing out of the second air outlet is larger than the amount of air flowing out of the first air outlet.
 5. The air circulation device, as recited in claim 3, wherein when the air distribution member is positioned in a second circulation position, the amount of air flowing out of the first air outlet is larger than the amount of air flowing out of the second air outlet.
 6. The air circulation device, as recited in claim 4, wherein when the air distribution member is positioned in a second circulation position, the amount of air flowing out of the first air outlet is larger than the amount of air flowing out of the second air outlet.
 7. The air circulation device, as recited in claim 3, wherein when the air distribution member is positioned in a neutral position, an amount of air flowing out of the first air outlet and an amount of air flowing out of the second air outlet are the same.
 8. The air circulation device, as recited in claim 4, wherein when the air distribution member is positioned in a neutral position, an amount of air flowing out of the first air outlet and an amount of air flowing out of the second air outlet are the same.
 9. The air circulation device, as recited in claim 5, wherein when the air distribution member is positioned in a neutral position, an amount of air flowing out of the first air outlet and an amount of air flowing out of the second air outlet are the same.
 10. The air circulation device, as recited in claim 6, wherein when the air distribution member is positioned in a neutral position, an amount of air flowing out of the first air outlet and an amount of air flowing out of the second air outlet are the same.
 11. The air circulation device, as recited in claim 1, further comprising a distribution mount configured for mounting to a fan motor mount secured to the housing for mounting a fan motor of the single fan unit in the air passage body, wherein the air distribution member is extended from the distribution mount at a middle portion of an air outlet opening of the air passage so as to divide the air outlet opening into the first air outlet and the second air outlet.
 12. The air circulation device, as recited in claim 2, further comprising a distribution mount configured for mounting to a fan motor mount secured to the housing for mounting a fan motor of the single fan unit in the air passage body, wherein the air distribution member is extended from the distribution mount at a middle portion of an air outlet opening of the air passage so as to divide the air outlet opening into the first air outlet and the second air outlet.
 13. The air circulation device, as recited in claim 3, further comprising a distribution mount configured for mounting to a fan motor mount secured to the housing for mounting a fan motor of the single fan unit in the air passage body, wherein the air distribution member is extended from the distribution mount at a middle portion of an air outlet opening of the air passage so as to divide the air outlet opening into the first air outlet and the second air outlet.
 14. The air circulation device, as recited in claim 4, further comprising a distribution mount configured for mounting to a fan motor mount secured to the housing for mounting a fan motor of the single fan unit in the air passage body, wherein the air distribution member is extended from the distribution mount at a middle portion of an air outlet opening of the air passage so as to divide the air outlet opening into the first air outlet and the second air outlet.
 15. The air circulation device, as recited in claim 9, further comprising a distribution mount configured for mounting to a fan motor mount secured to the housing for mounting a fan motor of the single fan unit in the air passage body, wherein the air distribution member is extended from the distribution mount at a middle portion of an air outlet opening of the air passage so as to divide the air outlet opening into the first air outlet and the second air outlet.
 16. The air circulation device, as recited in claim 10, further comprising a distribution mount configured for mounting to a fan motor mount secured to the housing for mounting a fan motor of the single fan unit in the air passage body, wherein the air distribution member is extended from the distribution mount at a middle portion of an air outlet opening of the air passage so as to divide the air outlet opening into the first air outlet and the second air outlet.
 17. A method of controlling air circulation of an air purifier, comprising: distributing a larger portion of air flow flowing out through one of a pair of air outlets than another one of the pair of air outlets of an air circulation device of the air purifier to form an air flow speed difference between the pair of air outlets to accelerate air circulation and provide an air vortex in a local space around the pair of air outlets.
 18. The method, as recited in claim 17, further comprising: positioning an air distribution member in a first circulation position, wherein an amount of air flowing out of the first air outlet is larger than an amount of air flowing out of the second air outlet.
 19. The method, as recited in claim 18, further comprising: selectively positioning the air distribution member in the first circulation position or a second circulation position, wherein in the second circulation position, the amount of air flowing out of the second air outlet is larger than the amount of air flowing of the first air outlet.
 20. The method, as recited in claim 17, further comprising: selectively positioning an air distribution member in a neutral position, a first circulation position or a second circulation position, wherein in the neutral position, an amount of air flowing out of the first air outlet and an amount of air flowing out of the second air outlet are the same, wherein in the first circulation position, the amount of air flowing out of the first air outlet is larger than the amount of air flowing out of the second air outlet, wherein in the second circulation position, the amount of air flowing out of the second air outlet is larger than the amount of air flowing of the first air outlet. 